RE: large arrays native element count wrong with Channel Access in EPICS 3.14.12

["Jeff Hill" <johill@lanl.gov>]

> I believe the client library clips all array get and subscription
> requests to the array's native element count

that?s correct

Jeff
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Jeffrey O. Hill           Email        johill@lanl.gov
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> -----Original Message-----
> From: Andrew Johnson [mailto:anj@aps.anl.gov]
> Sent: Tuesday, January 18, 2011 10:08 AM
> To: Jeff Hill
> Cc: EPICS core-talk
> Subject: Re: large arrays native element count wrong with Channel Access
> in EPICS 3.14.12
> 
> Hi Jeff,
> 
> On Tuesday 18 January 2011 10:31:05 Jeff Hill wrote:
> >
> > PS: Andrew, FWIW and referencing the know problems page, it is actually
> > possible to transfer large arrays w/o the patch. What doesn't work is
> > communication of the native element count when the client connects.
> 
> Right, as long as your client library is 3.14.12 and you're using the
> dynamic
> array sizing feature (which is still rare since it's a new feature).
> However
> I believe the client library clips all array get and subscription
> requests to
> the array's native element count (or maybe it rejects them if too large,
> I
> forget which), so I'm pretty sure that a client application using an
> older
> library version against an unpatched 3.14.12 IOC isn't going to be able
> to
> override the incorrect native count.  I haven't tried it though, so I
> might be
> wrong.
> 
> - Andrew
> --
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> scrutinize it closely, and unless the evidence is overwhelming, he will
> refuse to believe it.  If, on the other hand, he is offered something
> which affords a reason for acting in accordance to his instincts, he
> will accept it even on the slightest evidence.  -- Bertrand Russell